Effect of coating and intermittent warming on enzymes, soluble pectin substances and ascorbic acid of Prunus persica (Cv. Zhonghuashoutao) during refrigerated storage

The effect of 1% chitosan coating + polyethylene (PE) package, 1% chitosan + 0.5% CaCl2 coating + PEpackage, and 1% chitosan + 0.5% CaCl2 coating + PEpackage + intermittent warming on the enzymes and quality of Zhonghuashoutao fruits (Prunus persica) was studied during refrigerated storage (1 degreesC). The results showed that, compared to the control (CK) of water dip + PEpackage, all treatments had positive effectiveness on the inhibition of polyphenol oxidase, peroxidase (POD), ascorbic acid oxidases (ASA-POD) and polygalacturonase (PG) activities to some extent, and reduced the increase of soluble pectinefic substance. Results also showed that 1% chitosan + 0.5% CaCl2 + PEpackage + intermittent warming treatment significantly inhibited ASA-POD and PG activities, kept vitamin C at a high level, and reduced fruit sensitivity to chilling injury at the later stage of storage. (C) 2004 Elsevier Ltd. All rights reserved.